“Give Us a Bell” Means “Give Me a Call”

In casual Australian English, “Give us a bell when you get there” usually means “Phone me when you arrive”, not “Hand us a bell”. Bell refers to a telephone call, while the more surprising feature is that informal us can sometimes refer to the single speaker: me.

A: I should arrive around six.
B: Great. Give us a bell when you’re close.

The expression is relaxed and suits conversation between people who know each other. In a formal email, or when the listener may not know Australian or British colloquial English, “Please call me when you arrive” is clearer. “Give me a call” is also the more natural choice in American English. Do not automatically treat us as plural; the speaker and situation tell you who is meant.

https://dictionary.cambridge.org/dictionary/english/give-a-bell
https://www.queensland.com/au/en/plan-your-holiday/news-and-articles/translating-aussie-slang